Chronic active hepatitis in children. A clinical and immunological long-term study

Long-term outcome of autoimmune hepatitis in children

BACKGROUND AND AIM

Autoimmune hepatitis (AIH) is a chronic disease of unknown etiology, which usually progresses to cirrhosis if not diagnosed and treated promptly. Data on long-term follow up in children with AIH are scant. The aim of this study is to assess the long-term outcome of autoimmune hepatitis in children with respect to clinical and laboratory features at presentation.

METHODS

Data were extracted from the medical records of patients presenting over a 28-year period (1972-2000) to the Royal Children's Hospital, Melbourne, Australia. Additional information was obtained by interviewing patients, and their current physicians. Of the 30 patients (22 females, mean age 9 years) identified, 18 had type I, three had type II, four had autoimmune-polyendocrinopathy syndrome type 1, one had infantile giant-cell hepatitis associated with Coomb's-positive hemolytic anemia, and four were seronegative (antinuclear antibody (ANA), smooth muscle antibody (SMA) and liver-kidney microsomal antibody (LKM)).

RESULTS

Clinical features at presentation included hepatomegaly (86%), jaundice (66%) and splenomegaly (50%). Initial investigations revealed a median serum bilirubin level of 55 micromol/L (range 6-425), median aspartate aminotransferase level of 678 IU (range 70-2548), and abnormal clotting in 33% of patients. Liver biopsies were performed on all patients at presentation and 11 showed cirrhosis (36%). The mean follow-up period was 10.0 +/- 7.8 years with 43% being followed for > 10 years. Only two patients died and one required transplantation. Fourteen (50%) patients continue to be on low dose prednisolone with azathioprine, two (7%) are on prednisolone alone, and six (21%) are on no therapy. When the cirrhotic and non-cirrhotic patients were compared, the albumin level at presentation was significantly lower in the cirrhotic group (P=0.01). Of the patients who were cirrhotic at presentation, six (54%) remain compensated with a mean follow-up period of 8 years. All 24 patients currently under follow up are engaged in age-appropriate activities including school, part- or full-time work.

CONCLUSION

Autoimmune hepatitis has a favorable long-term outcome with a transplant-free survival rate of 90% over a mean period of 10.0 +/- 7.8 years (range: 0.5-23), and a normal or near-normal lifestyle irrespective of presenting clinical, laboratory or histological features.

Raised levels of antibodies to human viruses at the clinical onset of autoimmune chronic active hepatitis

Patients with autoimmune chronic active hepatitis (AICAH) often have very high titres of antibodies to rubella and/or measles virus. In the present study a young girl at the clinical onset of AICAH exhibited very high titres of antibodies against influenza viruses A and B, parainfluenza viruses, rubella virus and varicella-zoster virus. The titres normalized over 2 months except for rubella and varicella-zoster antibodies. Strong reactivities were seen against the rubella structural proteins E1, E2 and C in Western blot but IgM antibodies were not demonstrated. Total IgG was increased with normal ratios of subclasses. The IgG1 was the dominant antibody to E1 and E2, while IgG4 dominated the anti-C response. There was no significant shift in subclass reactivities over one year from onset. The polymerase chain reaction (PCR), using a nested primer set, was negative for rubella virus RNA in a liver biopsy obtained at the clinical onset and in peripheral blood mononuclear cells (PBMC) 1 year later. Co-cultivation experiments using PBMC and permissive cell lines were also negative for rubella virus. Hence, in the very early phase of AICAH there may be a transiently enhanced antibody response to various unrelated viruses.

Chronic hepatitis in childhood: the spectrum of the disease

During a multicentre study of chronic hepatitis in childhood diagnosed by biopsy, the spectrum of the disease has been evaluated in 196 consecutive patients, including 157 from Northern Italy and 39 from Southern Italy. Only 31% of patients in the former group and 27% in the latter were symptomatic when first seen: the majority of cases being seen after familial screenings for hepatitis B virus (HBV) markers or during intercurrent infections, thus suggesting that the frequency of chronic hepatitis in childhood might be largely underestimated in our area. In Southern and Northern Italy 83% of symptomatic and 95% of asymptomatic patients were hepatitis B surface antigen (HBsAg) positive in serum; only 15 (8.3%) of these children were born to mothers known to be HBsAg positive at delivery, but a high circulation of HBV was found in their families: in fact more than 65% of household contacts in Northern Italy and more than 90% in Southern Italy had serological evidence of past or ongoing HBV infection. These data indicate that, although familial screenings for HBV could have enhanced the percentage of HBsAg positive asymptomatic cases, chronic hepatitis in Italian children is mainly caused by HBV infection acquired in the familial setting through horizontal transmission. Such findings also emphasise the importance of mass vaccination of infants as the most effective means to prevent chronic type B hepatitis in childhood in our area. Among HBsAg positive children 55% had histological features of chronic active hepatitis and 85% were hepatitis Be antigen (HBeAg) positive in serum. Anti-HBe positive hepatitis was significantly more frequent in Southern than in Northern Italy in parallel with the significantly higher prevalence (17%) of hepatitis delta virus infection in that area. Of the 16 HBsAg negative cases included in the study three had autoimmune hepatitis, three Wilson's disease, one alpha1 antitrypsin deficiency, and nine had cryptogenic hepatitis, often associated to mild liver lesions resembling those seen in our adult patients with chronic non-A, non-B hepatitis unrelated to percutaneous exposure.

Duration of chronic active hepatitis and the development of cirrhosis

Chronic hepatitis implies that clinical and biochemical features of hepatitis have been present for at least 6 months; but irreversible liver damage may occur with subclinical disease suggesting that pathological features should also define chronicity. We examined 28 children with hepatitis B negative chronic active hepatitis to determine whether the severity of abnormal biochemical tests of liver function, raised serum immunoglobulin concentrations, and positive serum autoantibodies, which are characteristic features in immunosuppressant responsive disease, varied with the duration of symptoms. The pattern of abnormality in these patients was similar whether the disease had been present for less than three months, from three to 6 months, or for more than 6 months, and apart from lack of hyperbilirubinaemia was similar in patients presenting with complications of cirrhosis without previous symptoms of liver disease. Two children died of liver disease. The remainder showed a clinical, biochemical, and immunological response to prednisolone or azathioprine, or both. These drugs have now been withdrawn in 8 patients without relapse, and disease activity is completely suppressed in 13. Unfortunately, 15 survivors have definite cirrhosis and a further five have possible cirrhosis. Eight of 10 survivors with symptoms of more than 6 months duration before treatment have cirrhosis compared with two of 12 with symptoms of less than 6 months. It is suggested that consideration of this diagnosis at onset of symptoms and immediate immunosuppressant treatment after appropriate confirmatory investigations may reduce the incidence of cirrhosis in hepatitis B negative chronic active hepatitis in children.

IgM antibodies in sera from patients with chronic active hepatitis reacting with the measles virus matrix protein and nucleoprotein

The antigenic specificity of measles virus IgM antibodies in sera from patients with chronic active hepatitis not caused by hepatitis B virus has been examined. An immunosorbent column containing antihuman IgM covalently bound to Sepharose was used to pick up IgM from the sera. Radiolabelled measles virus antigens were then allowed to react with the IgM antibodies. The immune complexes were eluted and analysed by sodium dodecyl sulfate [SDS]-polyacrylamide gel electrophoresis. Four sera from patients with hepatitis B surface antigen [HBsAg]-negative chronic active hepatitis with high measles virus haemagglutination inhibition [HI] and complement fixation [CF] antibody titres and positive enzyme-linked immunosorbent assay [ELISA] for measles-virus-specific IgM were examined. The results were compared with those obtained using sera from patients with an acute measles virus infection and from healthy controls. In both patient groups, IgM antibodies with specificity against the matrix protein represented the major portion of the measles virus IgM. IgM antibodies against the measles virus nucleoprotein and probably against host-cell-derived actin were also present. The patient sera contained only traces of IgM antibodies with specificity against the measles virus haemagglutinin or fusion protein. No specific IgM antibodies were found in sera from healthy controls.

Seroimmunologic classification of chronic hepatitis in 57 children

A seroimmunologic evaluation of 57 children with chronic hepatitis is presented. Twenty-one patients had chronic persistent hepatitis and 36 had chronic active hepatitis. Serum samples obtained before treatment were tested for HBsAg, anti-HBs, anti-HBc, smooth muscle antibody, and antibody to endoplasmic reticulum. A persistently positive HBsAg was observed in the serum of 18 of the 21 patients with chronic persistent hepatitis. The chronic active hepatitis group was divided into three subgroups according to the presence of hepatitis B-virus markers (7 patients), smooth muscle antibody (10 patients), and endoplasmic reticulum antibody (9 patients). Determination of these markers could be useful for classifying children with chronic hepatitis.

Chronic active hepatitis in childhood with detection of liver-pancreas-specific autoantibodies

This paper describes a special form of chronic active hepatitis (CAH) with hypergammaglobulinemia in a ten-year-old girl. Because of unclear symptoms she was admitted to our hospital for exclusion of leukemia. However, further clinical and laboratory investigations suggested an autoimmune hepatitis although the typical antibodies could not be found in the immunofluorescence test. Only the detection of liver-pancreas-specific, complement-fixing autoantibodies (LP-antibodies) confirmed the diagnosis of an autoimmune hepatitis. Histology showed typical infiltrations of plasma cells and lymphocytes in the periportal area. LP-antibodies had been recently described in 20 adults with HBs-Ag-negative CAH[6]. To our knowledge this is the first report on LP-positive hepatitis in childhood. As a therapeutic response is likely, early immunosuppressive treatment is indicated.

Characterization of measles virus-specific antibodies in sera from patients with chronic active hepatitis

Measles virus-specific antibodies in sera from patients with HBsAg-negative chronic active hepatitis and raised antibody titres against measles virus, have been examined by crossed immunoelectrophoresis. The immunoprecipitates were further analysed by SDS-polyacrylamide gel electrophoresis. Five measles virus-specific precipitation lines were demonstrated using measles virus-infected cells solubilized with Triton X-100. The three major precipitation lines were analysed by SDS-PAGE and contained the virus polypeptides: nucleoprotein, NP (MW approximately 60 000); haemoagglutinin, H (MW approximately 80 000) and fusion protein F1 (MW approximately 40 000). Considerably higher amounts of antibodies against these three virus polypeptides were demonstrated in the patient sera than in sera from healthy controls. By SDS-PAGE analysis of radiolabelled immune complexes adsorbed to Sepharose-protein A, antibodies against five measles virus polypeptides: NP, H, F1, P protein (MW approximately 70 000) and matrix protein, M (MW approximately 37 000) were demonstrated in the patient sera.

Virus antibodies in the serum of patients with liver disease

Two hundred and twenty-six patients suspected of having liver disease were examined clinically, by a liver biopsy and laboratory test, according to a prospective scheme. Blood samples obtained just before the liver biopsy were coded and subsequently examined blindly, using the complement fixation test (CFT). The antigens were influenza A and B viruses, parainfluenza 1, 2, and 3, respiratory syncytial viruses, varicella, morbilli, cytomegalo and herpes simplex viruses. The sera were also examined by the CFT against Mycoplasma pneumoniae antigen. Antibodies against rubella virus were determined in a haemolysis-in-gel test. HBsAg and HBsAb were determined by a staphylococcal radioimmunoassay, and sera from patients with chronic active hepatitis (CAH) and chronic persistent hepatitis (CPH) were also examined for antibodies against hepatitis A virus by radioimmunoassay. Highly significant antibody titres against morbilli virus were found in patients with CAH and CPH. Patients with CPH or liver cirrhosis also had significantly higher titres against rubella virus than other groups. Some patients with liver granulomas had high titres against rubella virus. Only in one patient with CAH was a positive test for HBsAg found, and in one a positive test for HBsAb. Seven patients in the CAH and CPH groups had very high titres against both rubella and morbilli viruses.

Chronic viral hepatitis B in childhood. I. Clinical , Biochemical and histological results

The results of clinical, biochemical and histological studies in 26 children with chronic hepatitis B are reported. Most cases were detected when diagnostic procedures were arranged because of non specific abdominal complaints, by routing tests after acute hepatitis or multiple transfusions, and by examination of family members. Hepatomegaly was found in half of the cases, splenomegaly in a quarter. Other clinical signs were rarely seen. Among the biochemical findings, elevated serum transaminase activities were the most reliable indicators of chronic hepatitis. There was a significant difference of the mean transaminase activities between patients with CPH and CAH. In 15 children CPH was diagnosed histologically. 9 children had CAH, 2 children showed signs of MinH.

Measles virus specific precipitins in sera from patients with chronic active hepatitis

Measles virus specific antibodies in sera from 29 patients with chronic active hepatitis have been examined using standard serological tests and immunoelectrophoretic techniques. Significantly raised CF antibody titres against measles virus antigen were demonstrated in 50% of the sera. The major immunoprecipitate obtained by immunoelectrophoresis was shown to contain aggregates of measles virus nucleocapsids. Antibodies against the haemagglutinin antigen of the virus envelope were also raised and were demonstrated by line immunoelectrophoresis.